Conduit stub ups in concrete?

[eeprom]

I have been asked why I don't call out on my drawings details of concrete encasement for conduit stub ups. This particular situation is for three 2" conduits, rigid steel, coming out of the ground and going into a junction box mounted to the side of the building. The cables in the conduits are all low voltage, small conductors. I don't see any benefit in pouring concrete around the stub ups. Although I have seen this done. Can anyone explain what there is to gain by encasing conduit stub ups in concrete? Am I missing something?

Thanks
EE

 

[7anoter4]

According to NEC 344.30 Securing and Supporting:
RMC shall be installed as a complete system in accordance with 300.18 and shall be securely fastened in place and supported in accordance with 344.30(A) and (B).
In my opinion, if no other support is available a concrete foundation has to be provided
in order to support the conduits. A maximum force it has to be considered between outside possible abuse or the cable pulling effort.

 

[buzzp]

Our stub-ups are tied to concrete encased electrodes so we always have concrete around them but never use conduit. We use a PVC sleeve to protect it at the top of the concrete but that is as far as we go.
If your stub-ups are in conduit, there is no other requirement to support it outside of the normal requirements (3') from j-box or other that I know of. You can go to 5' as listed in the NEC if there are no structural members to tie the support to. So if your stub-ups are within 3' of the jbox, I think you are fine, otherwise, you may have to support it between the jbox and where it comes out of the ground. I think unistrut would be used before pouring a concrete pad.

I try to use only PVC underground with an occasional RMC galvanized elbow if the electricians tell me the pull may wear out the elbow. I don't like metal in the ground, even galvanized.

 

[eeprom]

I only use metal for risers and sharp bends underground. Otherwise it's all PVC. The conduits in question here are going up to a Jbox which is 3' off the ground. I don't see a need for a concrete reinforcement for the stub up.

EE

 

[buzzp]

I agree with you EEPROM.